Depends.
I've found rallying is the best way of honing your skills when the car is over the limit.
There are a whole host of skills which you'll pick up - drifting is relatively straightforward if it's just power oversteer. Rallying will help you with roll oversteer and lift off oversteer too. Plus handbrake turns, Scandinavian flicks and other techniques.
I would recommend you don't use your own car until you're proficient. The cars I've rallied are properly set up and easier to use.
Try your local rally school - there are a few dotted about.